Flathead Range & Glacier NP

Today's cooler and cloudier conditions are making for a generally stable snowpack. Surface obstacles remain a hazard at all elevations. You could trigger a small wet slide on a steep slope if you or your machine punches through the surface crust into the underlying moist snow. 

Saturday's temperatures were the warmest since the Atmospheric River impacted our area on December 5 and 6. Low elevations below the valley cloud deck remained cool, but temperatures above the stratus were uncomfortably above average. Upper elevation readings include 40F at the summit of WMR (6737 feet), 41F at Aeneas Ridge (7186 feet), and 43F at Snowslip (6950 feet). Badger Pass (6900 feet), just southeast of our advisory area, reached 50F with St Mary a balmy 58F. 

Temperatures overnight dipped below freezing at Aeneas Ridge following 31 hours above freezing. As of 0500, the above-freezing conditions continue for Stahl, Noisy, John F. Stevens Canyon, and Tunnel Ridge. 

This morning, we expect to find a thin surface crust capping perhaps 2-4 inches of wet snow on sunny aspects. Today's cooler and cloudier conditions diminish the rider-triggered wet loose slide hazard, and we have removed this from the problem list. However, a slight chance remains that you or your machine could punch through this crust and initiate a small wet slide on steep slopes. These should be harmless in size unless you are in a long-running gully or the debris carries you into a terrain trap.

We received two public observations on Saturday, a low total for a sunny holiday weekend. A party on the west face of the Great Northern accidentally triggered a wet loose slide on their descent. The slide appears relatively small, D 1.5, and harmless in its terrain. An experienced rider in the central Whitefish Range found dry settled powder on a northeast slope but intentionally triggered 5-10 cm deep wet loose slides on their southerly descent in the afternoon. They found the 12/7 crust stout at 7800 feet. I was in the Snyder Lake basin, basking in warm temperatures and listening to chunks of ice falling and trundling down the hillsides. No recent wet loose avalanche activity was observed.